This invention concerns a pushing device for the emerging of the bolt in locks which comprise at least: a handle axis which, with a radial arm, retracts a slide in the rotational maneuver to open the lock, a bolt, a connecting rod which drives the retraction of the bolt during said opening maneuver, a bolt tail, several trapping notches cut into the upper edge of this bolt tail, a latch plate sliding vertically, a latch belonging to the latch plate, a spring which drives the latch plate into a bottom position, where the latch is lodged in certain trapping notches, and which allows an upper position of this latch plate in which this latch is released from the trapping notches. Generally, there will also be a key mechanism able to actuate the emerging and the entering of the bolt.
It frequently happens that robbers enter homes while their residents are still inside.
This happens when one uses a conventional type of lock which is very widespread, having a slide and bolt, and where routinely or for comfort, displaying an excess of confidence, the locking of the door is entrusted solely to the slide, omitting to also lock the bolt with the key from the inside. Then the robber has only to retract the latch by the classical technique of pushing it with the edge of a credit card or the like, and he will be able to enter the dwelling. Closing of the bolt with a key from the inside would have prevented this possibility; however, this option has a negative side, namely, the impediment given a situation where the dwelling has to be exited in an emergency and the key is not ready to hand, or a child of young age is the one who has to perform the maneuver in a condition of excitement or nervousness.
These problems are solved by automatic and emergency-exit locks in which, when the door is brought up to the frame, the bolts are automatically closed, and there is an inside handle which is actuated to produce the total opening of the lock (latch and bolts). But these locks are very costly and require a very precise installation of the leaf and frame in order to function properly, so that they are only installed in a very small percentage.
The invention proposes to furnish a simple solution, one with similar functional performance for the more conventional and common locks mentioned in the beginning. In that the bolt can be removed from the inside by certain permanently available means, easy to operate and different from the key; and at the same time, they provide an emergency function which enables a total opening of the lock from the inside while the bolt is thrown.
Given this state of affairs, the present invention proposes a device which is applicable to the type of locks explained in the field previously specified for same; whose design has a special arrangement in that said handle axis has a coaxial lever which is rotationally coupled to same in a way that it turns along with it in the conventional direction of opening, yet it has an independent turning in the opposite direction, or anti-opening turning, whose lever has a peripheral lug which is applied, in relation to said anti-opening turning, against a fin of a rocker which is mounted spring-loaded and which has a projection which is applied against a heel belonging to a counter-rocker having a front piece which is applied, upward from below, against a transverse lug of said latch plate, there being a rotary rod which is mounted with free turning coaxially with said rocker and which has certain arms, a rocker, and a bolt, which are rotationally spaced out by an angle appropriately less than that needed to simultaneously make contact with the fin of the rocker in a state of rest and with the back of the bolt in a retracted condition, and this rotational angular difference remains, in the state of rest, between said fin and said rocker arm with an appropriate amplitude, depending on the vertical distance between the coupled and uncoupled positions of the latch in the trapping notches.
According to another characteristic of the invention, said rocker has a rotational operating run such that it reaches a flipped position in which its projection remains applied against the opposite side of the heel of the counter-rocker, at the same time as one wall of this counter-rocker is interfering with the start of the operating travel of a transverse flange of said connecting rod, which is necessary in order for this rod to drive the retraction of the bolt.
This arrangement of the proposed device enables the inside handle, preferably a doorknob, to perform an anti-opening turn from its position of rest with the bolt retracted. This anti-opening turn develops in two adjacent phases: a first one in which the peripheral lug of the lever pushes the fin of the rocker, making it travel the rotational angle which separates it initially from the rocker arm belonging to the rotational rod, during which travel the projection of the rocker pushes the heel of the counter-rocker and this flips, making its front end lift the transverse lug of the latch plate and produce the subsequent exiting of the latch from a respective front trapping notch of the tail of the bolt; and a second phase in which, in this state of release of the bolt, said fin of the rocker now pushes on said rocker arm of the rotary rod, making it flip, and its bolt arm drives the emerging of the bolt, during which the action of the projection of the rocker against the heel of the counter-rocker is maintained until, once the bolt has emerged, the projection of the rocker goes beyond the position of the heel of the counter-rocker and the latter recovers its initial nonflipped position and allows the latch to descend and enter into a respective rear trapping notch, for which it is aided by the driving of the corresponding spring against the transverse lug of the latch plate.
At the end of this process, said transverse flange of the connecting rod remains against said wall of the counter-rocker. Accordingly, if we now operate the handle in the opposite direction, the driving of this transverse flange against this wall will flip the counter-rocker, at the same time making the latch emerge from its trapped position in the tail of the bolt and its heel will retract enough so that the projection of the rocker elastically recovers its original position at the other side of this heel; at this moment, the path corresponding to the anti-opening turn has been cancelled and the further turning (now corresponding to the normal opening maneuver) will make the bolt be retracted by the connecting rod, while the bolt itself pushes against the bolt arm of the rotary rod so that it (being mounted with rotational freedom) recovers its initial position of the mechanism at rest.